– scramble by emerging economies to prop up their sagging currencies and avert credit defaults.

– In the late 1990s emerging-markets crisis, many of the countries with shaky finances were in Asia. Now many of them are dotted around Europe’s periphery. Countries such as Iceland, the Baltic countries, Hungary and Turkey ran up large foreign debts in recent years when credit flowed cheaply and easily. To different degrees, they’re struggling to repay or replace those debts in today’s dramatically changed world.

– Investors around the world are withdrawing their money from countries whose economies are vulnerable to a disruption in the supply of credit. As they flee to the relative safety of a newly resurgent dollar, uncertainties grow about how many emerging-market countries may need rescues, and how badly.

– Europe’s East has few banks of its own. Most are subsidiaries of large Western banking groups. Now that those are supported by their home governments, they are unlikely to let their Eastern units go bust.

Poland and Hungary

– The Polish zloty and Hungarian forint had their biggest weekly declines.

– On Wednesday, Hungary’s central bank had taken the dramatic step of raising interest rates by a steep three percentage points in order to prevent a run on its currency. The central bank’s steep lifting of already-high interest rates to 11.5% from 8.5% — against a recent tide of rate cuts elsewhere around the globe — didn’t significantly check the forint’s decline Wednesday. It fell 2.88% against the dollar, slightly less than some neighbors, contributing to a fall of nearly 10% so far this week and more than 21% so far this month.

– A run on the currency threatens the businesses and households because the cost of existing debts is soaring, while banks are choking off new lending. Many Hungarian companies and consumers also have borrowed heavily in euros, Swiss francs and other foreign currencies, where they could get lower interest rates and against which the forint had done well for years.

– Banks already are cutting back credit for small businesses and consumer purchases such as cars, fearing that debtors could struggle to repay as the economy sours.

– Already, the European Central Bank has lent Hungary €5 billion to help its banks raise foreign-currency funds — unprecedented aid from the ECB for a country that does not share the euro currency it controls. But there’s no sign the loan helped to restore investors’ confidence in the country.

– Hungary’s government, banks and companies need to repay or replace about €27 billion of debt to foreigners that falls due in the next 12 months. The country’s foreign-exchange reserves only come to about €17 billion, according to a report by Barclays Capital in London.

Estonia

– Estonia is headed for a two-year recession and won’t grow again until 2010, its central bank warned Wednesday, a far cry from the Baltic nation’s roaring annual growth of more than 10% for years until 2006.

Mexico

– Mexico bought $13.1 billion of pesos to keep the currency from falling further; it has had its worst decline since the country’s “tequila crisis” of 1994, when the United States put together a rescue package.

– The falling currencies are a sign that investors are losing confidence in those countries, and it makes their imports more expensive.

Brazil

– Brazil illustrates how indiscriminate the financial crisis has been in claiming victims. Unlike many nations, Brazil’s economy is relatively balanced, and its foreign borrowings have been relatively modest. Yet the country has still been squeezed by recent events. On Thursday, it eliminated its tax on foreign investments to remove an obstacle to capital inflows and bolster its currency, which has dropped 17.5 percent against the dollar this month.

IMF’srole

– The IMF stepped up its efforts to contain the expanding crisis, agreeing to a $2.1 billion rescue program with Iceland, whose financial meltdown triggered big losses for German and British banks. Belarus, Pakistan, Hungary and Ukraine have also asked the IMF for emergency loans.